Vehicles, and particularly all-terrain vehicles (ATV's) are intended for use on a variety of different surfaces, including dry pavement, dirt, grass, slippery surfaces such as ice, and gravel. Typically, such vehicles are driven by their back wheels, but allowance is made for providing torque also to the front wheels when the back wheels slip, as, for example, when a vehicle becomes mired in mud.
ATVs, in addition to being driven on a wide variety of surfaces, are used in a wide variety of applications. In some of these applications, i.e., off-roading or search and rescue operations, traction is paramount. When used for golf course maintenance or residential projects for example, it may be more important that the vehicle do as little damage to the surface upon which it is ridden as possible. Further, performance characteristics of vehicles with differential gearing are superior for some applications, while for others fixed drive axle performance is preferred.